Magic Matt

The jig would be brilliant if I had a circular saw... but I don't. Also, no power out in the shed, and no safe way to get power out there, hence any power tools I have need to be cordless.

Travis Perkins sounds like the ideal place to get stuff - they seem to have the righy ply in stock, and if they can cut to size also then that's going to be even better. It's an hour round trip, but probably worth it.

I read [color=#282828][font=helvetica, arial, sans-serif]21012L as 21'012 Litre... that's [/font][/color]2.8m wide, 4.48m high, 1.68m deep... holy crap that would be a big speaker!

Just tried it using an old HiFi - no, doesn't work... I mean you get sound out, but it just doesn't seem right. Using a small mixer worked far better, and was a lot easier to control the balance between the two signals, plus the VU meter also let me know if the signal was too hot and causing distortion..

[quote name='isteen' timestamp='1410614918' post='2551285']

Two cabs at 4 ohm, that's trouble, isn't it?

[/quote]

Electrically, no, they just need to be connected in series rather than parallel. That means a box or cable designed for that specific job.

Sound wise though, I'm not so sure. I think there are acoustic issues with running that kind of setup without a cross-over.

Of course, you could always have a crossover made up, so different signals are being sent to the 1x15" than the 4x10" speaker... then it would behave like one giant 4ohm speaker cabinet.

I always think it's a bit strange that people talk about wanting a vintage tone, then go and buy brand new pristine equipment... seems kind of backwards...

I can't afford to buy a router and a table saw... how would I radius the edges without a router!?
Everything is going to be done with hand tools, bar some stuff with a cordless jigsaw and a cordless drill/driver.

Will there really be no reinforcement needed if being assembled by a slightly cack-handed monkey?

...and I thought it was fracking causing all the earthquakes...

The best kind of speaker for Dubstep is a broken one... preferably without an amp.

Still tempted to put some small 12mm baton on the inside of the corners... because then I can trim the outer edges with 12mm quadrants and get a really nice look... just done it on a lid for the aquarium and I really like it.

I'm not too worried about the appearance of the wood faces, as I intend to cover it anyway, but obviously I don't want any voids.

Surely it would have to be an exceptionally bad piece of ply to have voids so large that loose material inside actually rattles and can be heard?

[quote name='dincz' timestamp='1410513603' post='2550174']
That's why I avoid drop tuning
[/quote]

So you'd have to remove the highpass protection filter... how would you stop the gravitational influence of the moon affecting your signal?

[quote name='xgsjx' timestamp='1410457585' post='2549700']
Everyone knows that regardless of the gig, you need 2 Ampeg 8x10 stacks.
[/quote]

...or one BFM Jack 12 ....

[quote name='Dad3353' timestamp='1410457166' post='2549689']
Clipping [i]is [/i]DC, a
[/quote]

No, it really isn't.

[quote name='Dad3353' timestamp='1410457166' post='2549689']
Speakers are happy when they're moving. They don't like being pinned up against one end of their travel or the other.
[/quote]

I've never managed to "pin" a speaker, or burn one out for that matter, with intentional application of DC (with the exception of exceeding speaker power ratings obviously). I'm not convinced you can actually pin them.

[quote]
[color=#282828][font=helvetica, arial, sans-serif]Ah. So a square wave with a period of 20 years is not the same as DC to a speaker..? OK[/font][/color]
[color=#282828][font=helvetica, arial, sans-serif][/quote][/font][/color]


Feel free to try it.

Read the comment about clipping being DC and cracked up! LOL! How could anyone think clipping is D.C.!?!?

That's a bit high for an acoustic guitar - when you're playing finger style it's about 80dB from 30cm away.

As for the lowest watts you can get away with, I've happily used a 15 watt amp with an acoustic guitar at a blues session and it was fine. It's all about tone though - there's no harm in using a larger amp and just keeping the volume down low, hence I still often use my 115 watt amp regardless, and just turn it down low.

True... I may be cheeky and ask if they have an offcut I could take as a sample, and see what it's like.

I have to really try not to rush into doing things and take my time over this. I'm keen to get started, but I don't want to waste money by being too eager.

Surely acceleration and deceleration are an issue whatever the waveform? If it's a low frequency sine wave, the movement required is slow. Lets use a 4mm travel for example - 100Hz sine wave, so the speaker can gently rock to and fro over that 4mm travel 100 times a second. No problem. A square wave isn't like that though - 100Hz square wave would require the speaker to move over that 4mm distance instantly, then stay there motionless for half a cycle, then instantly jump back, stay motionless for half a cycle, etc.... impossible! Speakers have mass, and require a force to move them, so there will always be a slight delay as it accelerates, moves, then decelerates - if the travel movement is fast enough, there will also be some bouncing due to the springy nature of the speaker cone material etc. - ok, only a little, but enough to prevent accurate reproduction of a square wave - what you get is a smoothed/rounded square with a little wobble.

I'm not sure what you're saying by "breaking down a square wave into its basic components"... square waves are the basic component! So much so that many battery-backup devices use square waves combined at different frequencies to artificially recreate a sine wave (DC to AC).

[quote name='NoirBass' timestamp='1410359738' post='2548535']
However, Its wireless and means I go through a lot of 9V batteries.
[/quote]

Side-note - rechargable NiMH last a lot longer than alkaline batteries on average. You can even fast-charge them during the gig so you start each set with a fresh... um... set.

Anything that has a headphone socket... and a set of nice big over-the-ear headphones!

Also, speakers can't produce proper square waves - your clipping will be dampened by the speaker mass and momentum. No matter how good the speaker is, you can't change the laws of physics. It's going to have to accelerate, and decelerate, at each "end" of the waveform, and trying to stop instantly is probably going to introduce artifacts into the sound.

[quote name='Sonic_Groove' timestamp='1410393251' post='2549089']
Does this all mean I can safely run a 12inch wizzy (no tweeter) cab with my Hotone Thunder Bass 5 watt without fear of damage?
[/quote]

Check the impedance and make sure your amp is happy with that rating.

What dictates volume is sensitivity rather than watts. If your 12" wizzy is as sensitive as the speaker in your Hotone it will sound about the same volume (ish), if not then it wont. I would be surprised if the sensitivity was the same though - bigger speakers = more mass to move = more energy needed to move it.

As far as I can tell, the only thing really relevant about watts on a speaker is how much heat it can dissipate before something bad happens.

If it clips it'll just sound like bad 80's punk.

Rent an amp - seriously. I've done that with a PA system before - never a good idea to rush into buying something that you'll be using for a long time, or being pressured into having to get something quickly just because you need it.

Yes, I've read through the Simplexx 12 plans a few times now - might actually be starting to sink in...
I'm very tempted by the two 1x12" route, rather than a single 15", because I can build them one at a time, which means the expense can be spread out a bit too.

[quote name='Bill Fitzmaurice' timestamp='1410387651' post='2549028']
Harmonics are multiples of the fundamental, so they're always higher in frequency, never lower.
[/quote]

I meant lower amplitude, rather than frequency...

With computer games, square wave output was all we had back in the early 80's! No fancy filters etc. just a square wave generator... or if you were really lucky... 3 of them... and if you were in luxury land you might also get one that generated pink or white noise! LOL!

[Quote]
[color=#282828][font=helvetica, arial, sans-serif]Clipping can toast tweeter voice coils, because what makes a square wave square is harmonics not present in a clean signal. [/font][/color]
[color=#282828][font=helvetica, arial, sans-serif][/quote][/font][/color]

[color=#282828][font=helvetica, arial, sans-serif]Are we talking harmonics that are still lower than the fundamental frequency of the square wave, but which could be pushing the tweeter beyond its Xmax, even though the woofer may be quite happy?[/font][/color]

You mean I'm not annoying enough here, you want me over there too!?

I'm working my way through reading the stuff in the FAQs etc. before I register, but I certainly will when I come to building the speaker. Thanks!